In this paper we examine the birefringence of buried optical waveguides written with femtosecond lasers in bulk fused silica glass. We report two modes of low and high birefringence associated with strong form birefringence and the orientation of nanogratings that align perpendicular to the writing laser polarization. The birefringence and waveguide losses are characterized over various laser exposure conditions to facilitate the fabrication of low-loss and compact wave retarders and polarization beam splitters for integration into polarization controlled circuits. Zero-order quarter-wave and half-wave retarders together with polarization beam splitters are demonstrated, all operating at telecom wavelengths. Integration of such devices is targeted for application in photonic quantum circuits.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.